Auto merge of #54703 - davidtwco:issue-52086, r=nikomatsakis

error message when trying to move from an Rc or Arc is ungreat

Fixes #52086.

r? @nikomatsakis

src/test/ui/borrowck/borrowck-move-out-of-overloaded-auto-deref.ast.nll.stderr

@@ -0,0 +1,9 @@
+error[E0507]: cannot move out of an `Rc`
+  --> $DIR/borrowck-move-out-of-overloaded-auto-deref.rs:17:14
+   |
+LL |     let _x = Rc::new(vec![1, 2]).into_iter();
+   |              ^^^^^^^^^^^^^^^^^^^ cannot move out of an `Rc`
+
+error: aborting due to previous error
+
+For more information about this error, try `rustc --explain E0507`.

src/test/ui/borrowck/borrowck-move-out-of-overloaded-auto-deref.mir.stderr

@@ -1,8 +1,8 @@
-error[E0507]: cannot move out of borrowed content
+error[E0507]: cannot move out of an `Rc`
   --> $DIR/borrowck-move-out-of-overloaded-auto-deref.rs:17:14
    |
 LL |     let _x = Rc::new(vec![1, 2]).into_iter();
-   |              ^^^^^^^^^^^^^^^^^^^ cannot move out of borrowed content
+   |              ^^^^^^^^^^^^^^^^^^^ cannot move out of an `Rc`
 
 error: aborting due to previous error
 

src/test/ui/borrowck/borrowck-move-out-of-overloaded-deref.nll.stderr

@@ -1,10 +1,10 @@
-error[E0507]: cannot move out of borrowed content
+error[E0507]: cannot move out of an `Rc`
   --> $DIR/borrowck-move-out-of-overloaded-deref.rs:14:14
    |
 LL |     let _x = *Rc::new("hi".to_string());
    |              ^^^^^^^^^^^^^^^^^^^^^^^^^^
    |              |
-   |              cannot move out of borrowed content
+   |              cannot move out of an `Rc`
    |              help: consider removing the `*`: `Rc::new("hi".to_string())`
 
 error: aborting due to previous error

src/test/ui/nll/issue-52086.rs

@@ -0,0 +1,24 @@
+// Copyright 2017 The Rust Project Developers. See the COPYRIGHT
+// file at the top-level directory of this distribution and at
+// http://rust-lang.org/COPYRIGHT.
+//
+// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
+// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
+// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
+// option. This file may not be copied, modified, or distributed
+// except according to those terms.
+
+#![feature(nll)]
+
+use std::rc::Rc;
+use std::sync::Arc;
+
+struct Bar { field: Vec<i32> }
+
+fn main() {
+    let x = Rc::new(Bar { field: vec![] });
+    drop(x.field);
+
+    let y = Arc::new(Bar { field: vec![] });
+    drop(y.field);
+}

src/test/ui/nll/issue-52086.stderr

@@ -0,0 +1,15 @@
+error[E0507]: cannot move out of an `Rc`
+  --> $DIR/issue-52086.rs:20:10
+   |
+LL |     drop(x.field);
+   |          ^^^^^^^ cannot move out of an `Rc`
+
+error[E0507]: cannot move out of an `Arc`
+  --> $DIR/issue-52086.rs:23:10
+   |
+LL |     drop(y.field);
+   |          ^^^^^^^ cannot move out of an `Arc`
+
+error: aborting due to 2 previous errors
+
+For more information about this error, try `rustc --explain E0507`.

src/test/ui/nll/move-errors.stderr

@@ -25,13 +25,13 @@ LL |     let s = **r;
    |             cannot move out of borrowed content
    |             help: consider removing the `*`: `*r`
 
-error[E0507]: cannot move out of borrowed content
+error[E0507]: cannot move out of an `Rc`
   --> $DIR/move-errors.rs:40:13
    |
 LL |     let s = *r;
    |             ^^
    |             |
-   |             cannot move out of borrowed content
+   |             cannot move out of an `Rc`
    |             help: consider removing the `*`: `r`
 
 error[E0508]: cannot move out of type `[A; 1]`, a non-copy array